Narrative:

Approaching mix master, 'cleared visual approach runway 13R, maintain 3000 ft until the mix master.' upon selecting flaps 5 degrees and slowing, received TCASII TA for target about 1 mi slightly right and 500 ft below. Began to search for traffic when TCASII gave a 'monitor vertical speed' RA (accompanied by vsi indication to not descend). We maintained straight and level until 'clear of conflict' was called. We still had not received any information from approach at this point. We were now at the mix master, slightly behind in confign. I called for landing gear down and flaps 15 degrees to continue for runway 13R. The aircraft was not in sight and as I commenced a left turn, TCASII gave us another RA to climb accompanied by a vsi indication showing the conflicting traffic just 300 ft directly below and requiring a 1200 FPM climb. I climbed to approximately 3400 ft until hearing 'clear of conflict' and then observed the traffic on TCASII well behind. I believe I heard ATC communication to us about the traffic and that they had us in sight. As a result of our position, we needed to swing wide and select flaps 40 degrees to comply with stabilized approach requirements (power added about 800 ft AGL). Our unintentional deviation was that we did not initiate/complete the final descent checklist until 500-300 ft AGL. My main concern with this event was that this was the second time in my career I had to comply with TCASII RA and sits were nearly identical (first was when I was in military). In both cases, we were talking to approach when the traffic in question was VFR with the tower (or someone else) never pointed out to us, but supposedly had us in sight. Hope this could help with a bit better coordination between agencies in the future. Not sure we shouldn't have executed a go around, but what might have been above us? Callback conversation with reporter revealed the following information: reporter advised that the 'mix master' is a local term for a freeway interchange. The one in question is approximately 9 mi northwest of the airport. The reporter advised that the traffic in question was a VFR training flight, single engine cessna being worked by dal tower. This was verified from a call to the TRACON (D10) after the incident. The D10 supervisor stated that dal had not effected coordination of the cessna's position or intention to the approach controller prior to the incident.

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Original NASA ASRS Text

Title: B737 FLC EXECUTE TCASII RA MANEUVER WHILE ON VISUAL APCH TO DAL RWY 13R.

Narrative: APCHING MIX MASTER, 'CLRED VISUAL APCH RWY 13R, MAINTAIN 3000 FT UNTIL THE MIX MASTER.' UPON SELECTING FLAPS 5 DEGS AND SLOWING, RECEIVED TCASII TA FOR TARGET ABOUT 1 MI SLIGHTLY R AND 500 FT BELOW. BEGAN TO SEARCH FOR TFC WHEN TCASII GAVE A 'MONITOR VERT SPD' RA (ACCOMPANIED BY VSI INDICATION TO NOT DSND). WE MAINTAINED STRAIGHT AND LEVEL UNTIL 'CLR OF CONFLICT' WAS CALLED. WE STILL HAD NOT RECEIVED ANY INFO FROM APCH AT THIS POINT. WE WERE NOW AT THE MIX MASTER, SLIGHTLY BEHIND IN CONFIGN. I CALLED FOR LNDG GEAR DOWN AND FLAPS 15 DEGS TO CONTINUE FOR RWY 13R. THE ACFT WAS NOT IN SIGHT AND AS I COMMENCED A L TURN, TCASII GAVE US ANOTHER RA TO CLB ACCOMPANIED BY A VSI INDICATION SHOWING THE CONFLICTING TFC JUST 300 FT DIRECTLY BELOW AND REQUIRING A 1200 FPM CLB. I CLBED TO APPROX 3400 FT UNTIL HEARING 'CLR OF CONFLICT' AND THEN OBSERVED THE TFC ON TCASII WELL BEHIND. I BELIEVE I HEARD ATC COM TO US ABOUT THE TFC AND THAT THEY HAD US IN SIGHT. AS A RESULT OF OUR POS, WE NEEDED TO SWING WIDE AND SELECT FLAPS 40 DEGS TO COMPLY WITH STABILIZED APCH REQUIREMENTS (PWR ADDED ABOUT 800 FT AGL). OUR UNINTENTIONAL DEV WAS THAT WE DID NOT INITIATE/COMPLETE THE FINAL DSCNT CHKLIST UNTIL 500-300 FT AGL. MY MAIN CONCERN WITH THIS EVENT WAS THAT THIS WAS THE SECOND TIME IN MY CAREER I HAD TO COMPLY WITH TCASII RA AND SITS WERE NEARLY IDENTICAL (FIRST WAS WHEN I WAS IN MIL). IN BOTH CASES, WE WERE TALKING TO APCH WHEN THE TFC IN QUESTION WAS VFR WITH THE TWR (OR SOMEONE ELSE) NEVER POINTED OUT TO US, BUT SUPPOSEDLY HAD US IN SIGHT. HOPE THIS COULD HELP WITH A BIT BETTER COORD BTWN AGENCIES IN THE FUTURE. NOT SURE WE SHOULDN'T HAVE EXECUTED A GAR, BUT WHAT MIGHT HAVE BEEN ABOVE US? CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: RPTR ADVISED THAT THE 'MIX MASTER' IS A LCL TERM FOR A FREEWAY INTERCHANGE. THE ONE IN QUESTION IS APPROX 9 MI NW OF THE ARPT. THE RPTR ADVISED THAT THE TFC IN QUESTION WAS A VFR TRAINING FLT, SINGLE ENG CESSNA BEING WORKED BY DAL TWR. THIS WAS VERIFIED FROM A CALL TO THE TRACON (D10) AFTER THE INCIDENT. THE D10 SUPVR STATED THAT DAL HAD NOT EFFECTED COORD OF THE CESSNA'S POS OR INTENTION TO THE APCH CTLR PRIOR TO THE INCIDENT.

Data retrieved from NASA's ASRS site as of July 2007 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.